Analysis of upper limb muscle strength in the early phase of brain stroke

Purpose: The aim of this study was to determine the muscles with the lowest strength in non-affected (non-A) and affected upper limb (A), to assess differences between men and women and to correlate these values with age in patients after stroke. Methods: Sixty patients (40 male, 20 female), hospitalized in Neurorehabilitation Ward, 1-2 weeks after stroke, were included in the study. Their age ranged from 50 to 80 years with a mean (sd) of 65.5 (18.7) years. Muscle force values from upper limb muscles were measured using the MicroFet 2 hand-held dynamometer. The results are given in Newtons [N], mean values of muscular force, effect sizes and confidence intervals are displayed as Cohen's d and 95% CI were determined. Moreover, we made the coefficients correlation for differences in muscular force versus the Rivermead Motor Assessment (RMA) arm section. Results: Strength of (A) upper limb in comparison to (non-A) was 39% weaker. The severely affected muscle groups were the shoulder flexion 41% (women) versus 46% (men); elbow flexion 39% (women) versus 31% (men); wrist extension 36% (women) versus 42% (men). No significant correlations were found between muscle strength results and RMA or age. Conclusions: Muscle force of (A) upper limb after stroke demonstrates a 39% decrease. Men show more significant decrease than women (40% vs. 35%). Functional assessment in RMA values shows the better results in women (4.9 +/- 4.1) than men (3.4 +/- 3.2).